<?php 

$key = current(array_keys($_POST));  /*取当前项的键值 不加current时是：0 => string 'username*/

function checkUsername()
{
	/*var_dump($_POST);  post输入的内容*/

	$username = $_POST['username'];

	$preg="/^[A-z0-9]{5,7}$/";

	$c=preg_match($preg, $username);

	if (!$c) {
		$arr = array(
			'error'=>1,
			'info'=>'长度是5-7位的字母或数字',
			);
		echo json_encode($arr);
		exit;
	}

	$users = include_once './user.php';

	foreach ($users as $user) {
		if ($user['username']==$username) {
			$arr = array(
			'error'=>1,
			'info'=>'用户名已存在',
			);
			echo json_encode($arr);
			exit;
		}
	}


	$arr = array(
			'error'=>0,
			'info'=>'用户名可用',
			);
		echo json_encode($arr);
		exit;
}


function checkEmail()
{

	$username = $_POST['email'];

	$preg="/^[a-zA-Z0-9_-]+@[a-zA-Z0-9_-]+(\.[a-zA-Z0-9_-]+)+$/";

	$c=preg_match($preg, $username);

	if (!$c) {
		$arr = array(
			'error'=>1,
			'info'=>'长度是5-7位的字母或数字',
			);
		echo json_encode($arr);
		exit;
	}

	/*$users = include_once './user.php';

	foreach ($users as $user) {
		if ($user['username']==$username) {
			$arr = array(
			'error'=>1,
			'info'=>'用户名已存在',
			);
			echo json_encode($arr);
			exit;
		}
	}*/


	$arr = array(
			'error'=>0,
			'info'=>'邮箱可用',
			);
		echo json_encode($arr);
		exit;
}

function checkPassword()
{

	$username = $_POST['password'];

	$preg="/^\w{6,}$/";

	$c=preg_match($preg, $username);

	if (!$c) {
		$arr = array(
			'error'=>1,
			'info'=>'密码是6位以上的字母或数字',
			);
		echo json_encode($arr);
		exit;
	}

	/*$users = include_once './user.php';

	foreach ($users as $user) {
		if ($user['username']==$username) {
			$arr = array(
			'error'=>1,
			'info'=>'用户名已存在',
			);
			echo json_encode($arr);
			exit;
		}
	}*/


	$arr = array(
			'error'=>0,
			'info'=>'密码可用',
			);
		echo json_encode($arr);
		exit;
}


function checkOther()
{

	$arr = array(
			'error'=>3,
			'info'=>'传的参数不正确',
			);
		echo json_encode($arr);
		exit;
}




switch ($key) {
	case 'username':
		checkUsername();
		break;
	case 'email':
		checkEmail();
		break;
	case 'password':
		checkPassword();
		break;
	
	default:
		checkOther();
		break;
}

 ?>